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Idaho History Timeline
Important Dates, Events, and Milestones in Idaho
Offers a chronological timeline of important dates, events, and milestones in Idaho history.
Bordered by the Canadian province of British Columbia to the north and the U.S. states of Montana and Wyoming to the east, Utah and Nevada to the south, and Oregon and Washington to the west, Idaho is twice as large as the six New England states combined. From 12,500–6,000BCE, the area now known as Idaho is likely home to big-game-hunting Paleo-Indian groups, such as the Clovis, Folsom, and Plano cultures. Around 6,000 BCE native cultures establish permanent settlements. The predominant tribes of the region include the Nez Perce and the Coeur d’Alene in the north and the Northern and Western Bannock in the south
18th Century Idaho History Timeline
1743 - Discovery of the Rocky Mountains somewhere in the vicinity of Yellowstone Park made by Pierre De la Verendrye, while in search of a western sea.
19th Century Idaho History Timeline
1803 - The Louisiana Territory purchased by the United States from France for $15 million.
1805 - Captains Meriwether Lewis and William Clark discover Idaho at Lemhi Pass, and cross into north Idaho over the Lolo Trail August 12.
1806 - Lewis and Clark spend more than six weeks with the Nez Perce Indians in the Kamiah area before returning eastward across the Lolo Trail.
1809 - Britain opens the first trading post in Idaho. David Thompson constructs Kullyspell House by Lake Pend Oreille. First establishment erected in the Northwest, built for the Northwest Fur Company.
1811 - Pacific Fur Company expedition, the Astorians, explore the Snake River Valley on their way to the Columbia River. Led by Wilson P. Hunt, the westward journey discovers the Boise Valley.
1812 - Donald Mackenzie establishes a winter fur trading post at Lewiston for the Astorians.
1813 - John Reid starts fur trading post on the lower Boise River, but Bannock Indians wipe it out in 1814.
1820 - Treaty between Spain and US establishes the southern boundary of Idaho (Oregon Territory) at 42nd parallel.
1823 - Battle fought in Lemhi Valley between men of the Snake River country expedition and the Piegan Indians.
1827 - Rendezvous at Bear Lake for fur trading.
1829 - Rendezvous held at Pierre's Hole, now known as the Teton basin, where hundreds of mountain men and fur trappers congregated.
1830 - Rendezvous with the Indians held on the Blackfoot River, where competition in fur trading became intensely keen.
1831 - Fur trappers of the Rocky Mountain Fur Company, led by Kit Carson, winter on the Salmon River.
1836 - Henry Harmon Spalding establishes a Nez Perce Indian mission at Lapwai.
1840 - Father Pierre Jean de Smet begins missionary work in Idaho.
1842 - Father Point establishes the Jesuit Coeur d' Alene Mission of the Sacred Heart near Saint Maries. The Mission moves to a site near Cataldo in 1846, and is transferred in 1877 to Desmet where it stands today.
1843 - Oregon Trail established in Idaho, which crossed the border near Montpelier, passed by Fort Hall, then westward south of the Snake River to the ford below Salmon Falls, then to Fort Boise, crossing the Snake River into Oregon.
1848 - Oregon Territory established.
1852 - French Canadians discover gold on the Pend Oreille River.
1854 - Twenty-one emigrants led by Alexander Ward massacred in Boise Valley by the Snake River Indians. This event leads to the closing of Fort Boise the next summer and Fort Hall in 1856.
1856 - Fort Hall closed.
1857 - Oregon's eastern boundary (Idaho's western boundary) established by Oregon constitutional convention.
1858 - Bannock Indians attacked the Mormons at Fort Lemhi, killing two and driving the remaining back to Utah.
1859 - Oregon admitted as a state, all of Idaho included in Washington Territory.
1873 - Coeur d'Alene Indian Reservation set aside by President Grant for the Coeur d'Alene and Spokane Indians.
1882 - Northern Pacific railroad completed across the northern part of the Territory. Construction began on the New York Canal in Ada County.
20th Century Idaho History Timeline
1914 - Moses Alexander elected first Jewish governor in the United States.
1918 - Non-Partisan League takes over Idaho Democratic primary September 3, subsequently Idaho's primary nominating system is abandoned for twelve years.
1930 - Idaho population: 445,032.
1937 - Open primary system does away with requirement for declaration of party affiliation.
1944 - Mountain Home Army Air Field officially opened.
1949 - National Reactor Testing Station near Arco established.
1952 - Anderson Ranch Dam completed.
1959 - Brownlee Dam completed on the Snake River.
1962 - Lewis and Clark highway (US 12) in the Lochsa Canyon completed.
1968 - Hell's Canyon Dam completed.
1969 - Annual legislative sessions commence.
Legislature imposes temporary 4 1/2 percent sales tax to cover state deficit.
1988 - Voters pass constitutional amendment removing prohibition against legislature authorizing a state lottery.
1998 - Picabo Street wins gold medal in giant slalom at Olympic winter games.
1999 - First shipment of nuclear waste leaves INEEL for permanent storage at the federal Waste Isolation Pilot Project in New Mexico.
21st Century Idaho History Timeline
2000 - 559,183 acres burned in forest fires
2001 - 24 counties declared drought disaster areas
2003 - Longest legislative session in history lasted 118 days
2005 - Nez Perce water agreement ratified, tribe received annual rights to 50,000 acre-feet water from Clearwater River and $80 million cash.
2007 - Idaho had more wildfires burning than any other state, over 1.5 million acres damaged.
2010 - Nine missionary Baptists from Idaho were arrested and faced kidnapping, trafficking charges in Haiti for attempted rescue of 33 Haitian children traumatized by earthquake, they were later released
2010 - Idaho became first state to pass law rejecting federal mandatory health insurance requirement